Error Handling

Introduction

Robust apps wrap every MongoDB call in error handling. Drivers throw rich errors (MongoServerError, WriteConcernError) you can switch on for retries, fallbacks and user feedback.

Syntax reference

try {
  await db.users.insertOne({ email });
} catch (e) {
  if (e.code === 11000) return { error: "email exists" };
  throw e;
}

Best practices

• Always handle the unique-index violation code 11000.
• Add retry-with-backoff for transient network errors.